In order to effectively generate printed images using the various ink transfer techniques and systems (with primary but not necessarily exclusive reference to thermal inkjet technology), ink-receiving print media materials must be employed which are capable of efficiently accomplishing this goal. Ideally, to achieve maximum efficiency, print media materials should be able to provide numerous advantages and benefits including but not limited to (1) a high level of light-fastness, with the term xe2x80x9clight-fastnessxe2x80x9d being generally defined herein to involve the capacity of a print media product to retain images thereon in a stable fashion without substantial fading, blurring, distortion, and the like over time in the presence of natural or madexe2x80x94made light; (2) rapid drying times in order to avoid smudging and image deterioration immediately after printing is completed due to contact with physical objects and the like; (3) the fast and complete absorption of ink materials in a manner which avoids image distortion caused by color bleed (namely, the undesired migration of multi-colored ink components into each other) and related difficulties; (4) a highly humid-fast character (with the term xe2x80x9chumid-fastxe2x80x9d being generally defined to involve the ability of a print media product to produce a stable image with little or no fading, run-off, distortion, and the like when the image is placed in contact with moisture, humidity, and the like (also known in a substantially equivalent fashion as xe2x80x9cwater-fastnessxe2x80x9d)); (5) the generation of xe2x80x9ccrispxe2x80x9d images with a distinct and defined character; (6) the ability to produce printed products which are substantially xe2x80x9csmear-fastxe2x80x9d, with this term being generally defined to comprise the production of images that will not exhibit smearing, blurring, and the like when rubbed or otherwise physically engaged with a variety of objects ranging from the components of the printing apparatus being employed to the print operator""s hands, fingers, and the like; (7) the control of an undesired condition known as xe2x80x9cink-coalescencexe2x80x9d which is defined herein to involve a phenomenon wherein wet ink droplets applied to a printing medium fail to spread sufficiently to eliminate the unprinted (e.g. open) space between the droplets, thereby causing significant image deterioration problems which are primarily manifested by the increased xe2x80x9cgraininessxe2x80x9d of the image; (8) the capacity to generate printed images with desired levels of gloss wherein the final product is characterized by uniform gloss levels throughout the entire image in order to achieve a professional and aesthetically-pleasing printed media sheet; (9) the ability to attain a high level of consistency during large-scale production regarding the overall surface characteristics of the completed media products; (10) low material costs which enable the print media products of interest to be employed for mass market home and business use; (11) chemical compatibility with a wide variety of ink formulations which leads to greater overall versatility; (12) excellent levels of image stability and retention over long time periods; (13) minimal complexity from a production, material-content, and layer-number standpoint (with as few required layers as possible being desirable) which leads to reduced fabrication costs and greater product reliability; and (14) a high level of gloss-control which is achievable in a rapid and effective manner during production through only minor adjustments in the manufacturing process. The term xe2x80x9cgloss-controlxe2x80x9d is generally defined herein to involve the ability, during fabrication, to generate a print media product having high gloss levels for the production of photographic quality images if desired, a semi-gloss character if needed, or other gloss parameters. In particular, the manufacturing process should be highly controllable in order to achieve a variety of different gloss characteristics without requiring major adjustments in processing steps and materials.
A need remains for print media materials (namely, ink-receiving sheets or structures) which are able to capture and retain clear, distinct, and accurate images thereon that are likewise characterized by a number of specific benefits in combination. These benefits include but are not limited to items (1)-(14) recited above both on an individual and simultaneous basis in a substantially automatic manner (with the simultaneous achievement of such goals being of particular importance and novelty). The attainment of these objectives is especially important regarding the following specific items: a high level of humid-fastness, excellent light-fastness, an effective level of ink-coalescence control in order to prevent excessive xe2x80x9cgraininessxe2x80x9d (namely, the undesired appearance of large xe2x80x9cgrain-likexe2x80x9d elements in the printed product), and the generation of clear, durable, smear-fast, and distinct printed images.
The following discussion shall constitute a brief and non-limiting general overview. More specific details concerning particular embodiments and other important features (including a recitation of preferred construction materials, chemical ingredients, quantities, and the like) will again be recited in the Detailed Description section set forth below.
In order to produce a preferred print media product in accordance with the present disclosure, a substrate is initially provided. Supported by the substrate is at least one ink-receiving layer (also characterized herein as a xe2x80x9ccoating formulationxe2x80x9d during the production stages thereof), with the ink-receiving layer being produced from a plurality of binders. The plurality of binders (also characterized herein as a xe2x80x9cbinder blendxe2x80x9d) will, in a preferred embodiment, involve a First Binder comprised of gelatin, a Second Binder comprised of a poly(vinyl alcohol-ethylene oxide) copolymer, and a Third Binder comprised of a poly((styrene)-(n-butyl acrylate)-(methyl methacrylate)-(2-(tert-butylamino) ethyl methacrylate)) copolymer.
At least one additional binder may optionally be employed within the foregoing plurality of binder compositions which is different from the First Binder, Second Binder, and the Third Binder. Likewise, the above-mentioned binder blend (with or without any additional binders) may be combined with one or more other ingredients including but not limited to at least one pigment. The employment of one or more pigments shall be considered optional and may include a wide variety of different materials as outlined in considerable detail below.
The claimed ink-receiving layer may likewise be employed as the sole material layer supported by the substrate in the print media product or can be used in combination with one or more additional material layers thereover or thereunder without limitation. For instance, at least one additional material layer can be positioned between the substrate and ink-receiving layer as an xe2x80x9cintermediatexe2x80x9d or xe2x80x9cmedialxe2x80x9d structure. No limitations or restrictions shall exist involving the additional material layer which can contain a wide variety of different compositions therein including but not limited to pigments, binders, mixtures thereof, and other xe2x80x9csupplementalxe2x80x9d ingredients as recited below.
Also to be outlined in the Detailed Description section are various methods for producing a print media product wherein the above-mentioned substrate is initially provided. Formed thereon (e.g. over and above the substrate) is the ink-receiving layer discussed above. An optional method step is the providing of at least one or more additional material layers over or under the ink-receiving layer. For example, at least one additional material layer may be formed as an xe2x80x9cintermediatexe2x80x9d or xe2x80x9cmedialxe2x80x9d structure between the substrate and ink-receiving layer as previously described.
Again, the foregoing discussion shall not limit the invention in any respect and represents only a general overview of certain materials, structures, and methods employed in connection with the claimed print media products.